Barack Obama’s tough new environmental rules for power plants confirm that Australia’s minimum greenhouse emission reduction target is inadequate by global standards, according to experts.

The US Environmental Protection Agency (EPA) has finalised new regulations to cut carbon pollution from power plants by 30% by 2030 compared with 2005 levels.

According to the former Labor government’s expert climate adviser, Professor Ross Garnaut, the move confirms the judgment of Australia’s independent Climate Change Authority that the country’s target – to reduce reducing total greenhouse emissions by 5% by 2020 compared with 2000 – is too low and out of step with international efforts.

It also found the costs of such an increase would be “manageable” – involving a reduction of only 0.02% in annual average income growth per person – compared with meeting the 5% target, under “effective” domestic policies, especially if Australia bought some carbon abatement internationally.

But the government said its immediate priority was to abolish the former Labor government’s carbon pricing scheme and implement its own grants-based policy designed to meet only a 5% target.

Garnaut said the latest US move again showed that a 5% target for 2020 was “out of step with international action”. It showed the US would probably meet, and could perhaps overshoot, its overall 2020 target to reduce greenhouse emissions by 17%.

The new US policy – evidence of the high priority climate change issues are being given by the US administration – comes as Tony Abbott departs on a trip that will include his first bilateral talks with the US president, who is reported to “routinely” raise the issue in discussions with other world leaders.

The Grattan institute’s energy policy director, Tony Wood, also said the US move put pressure on Australia to increase its efforts.

“It means the United States is really back at the table in terms of climate change negotiations internationally,” Wood told the ABC.

“The Australian government may need to look very closely at whether it needs to increase its 5% target by 2020 … and beyond that it means Australia will have to put much more effort into what commitments we will make going beyond 2020,” he said.

The environment minister, Greg Hunt, has said the government would meet its 5% target through its Direct Action plan and “any additional targets will be reviewed in 2015 in the lead-up to the Paris conference, as has been our longstanding position”. But the Paris conference will negotiate an agreement to take effect after 2020, not the 2020 targets discussed in the authority’s report.

Despite the Coalition’s pre-election bipartisan commitment to increase Australia’s 2020 emissions reduction target to up to 25% under a specific set of conditions for global action set down in 2009, the prime minister has claimed since the election the government had made no commitments to go further than 5%.

“We have made one commitment and one commitment only, which is to reduce our emissions by 5% … we have never made any commitments to any binding targets over and above that, in the absence of absolutely clear evidence that other countries are going to take a very serious like approach,” Abbott said last year.

But – even before the latest US move – the authority said Australia’s 5% target was much weaker than targets set by countries including the US, Britain and Norway, and pointed out countries such as China are also stepping up emission reduction efforts.

It said all the previously agreed 2009 conditions for moving above a 5% target have been met, as have many of the conditions for a 15% target.

As well as abolishing the independent Climate Change Authority and the carbon pricing scheme itself, the government is also seeking to abolish the Clean Energy Finance Corporation and the Australian Renewable Energy Agency.

It appears likely to win the repeal of the existing carbon pricing laws in the new Senate, which sits from July, but the fate of its alternative Direct Action policy remains unclear.

The chief executive of the Climate institute, John Connor, said that even if Direct Action was implemented “it will have little chance of meeting even the minimum 5% target”.

Hunt said he “welcomed” the US position and said that if the Australian target was compared against the same base year as America's then the domestic target amounted to a 12% cut”.

“I’ll let the two leaders reflect on their own agenda,” he said when asked about next week’s meeting between Obama and Abbott.

“I have discussed with the US ambassador common approaches in reducing emissions ... and we want a good global agreement, and America’s role in this we welcome, clearly and categorically,” Hunt told the ABC.